The ability to measure and understand protein fluorescence depends on the development of light sources which can excite the intrinsic aromatic amino acids, tryptophan, tyrosine, and phenylalanine. In recent years the time-resolved study of protein fluorescence has been limited to the excitation of tryptophan and tyrosine. The availability of the shorter wavelength, 265nm light source, allows for the excitation of phenylalanine which until recently has been limited. In this thesis the direct excitation of phenylalanine is demonstrated, using pulsed light emitting diodes, and the bi-exponential nature of its fluorescence decay is investigated, and the effect of pH on the fluorescence lifetimes. One of the major difficulties with the study of proteins is the lack of immobilisation techniques for the study of proteins at the single-molecule level, which provide little perturbation of the protein. To try to achieve this, the fabrication of novel molecular nanoenvironments, based on sol-gel techniques, which allow control and enhancement of protein fluorescence has been developed. In this thesis the application of sol-gel techniques is demonstrated for the environment sensitive trimeric form of allophycocyanin (APC) at both the ensemble and single-molecule level. The optimisation of the sol-gel technique as a generic approach to entrapment of proteins was developed using the environment sensitive probe 6-propionyl-2-(N,N-dimethylamino)naphthalene (PRODAN), which enabled monitoring of the hydrolysis and methanol removal stage of the process. For earlier diagnosis, ultra sensitive monitoring and breakthroughs in understanding the causes of many diseases, we urgently need to develop clinical single molecule sensing. Downstream, this might be accomplished by means of the fluorescence nanosecond/nanometre microscopy of single biomacromolecules.